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United States Patent | 5,684,868 |
Alexander | November 4, 1997 |
One or more lines of a communication terminal are monitored to determine blocked calls by detecting times of incoming calls. A signal corresponding to the pattern of incoming calls is generated from the detected times. After detection of the starting time of an all lines are busy state, an estimate of blocked calls is formed from the incoming call pattern signal and the detected start of the all lines are busy state.
Inventors: | Alexander; Robert C. (Columbia, VA) |
Assignee: | BTG USA, Inc. (Gulph Mills, PA) |
Appl. No.: | 240698 |
Filed: | January 4, 1996 |
PCT Filed: | November 6, 1992 |
PCT NO: | PCT/US92/09714 |
371 Date: | January 4, 1996 |
102(e) Date: | January 4, 1996 |
PCT PUB.NO.: | WO92/09714 |
PCT PUB. Date: | November 6, 1992 |
Current U.S. Class: | 379/140; 379/32.04; 379/111; 379/112.01; 379/164 |
Intern'l Class: | H04M 015/00; H04M 015/08 |
Field of Search: | 379/34,112,113,111,130,131,140,141,164,165,377,383,221 370/16,252,253 |
4250354 | Feb., 1981 | Karras | 379/34. |
4559416 | Dec., 1985 | Theis et al. | 379/34. |
4712230 | Dec., 1987 | Rice et al. | 379/112. |
5230017 | Jul., 1993 | Alexander | 379/140. |
5249223 | Sep., 1993 | Vanacore | 379/113. |